1. Field of the Invention
The present invention relates to a fluidized bed process for the oxidative dehydrogenation of organic compounds to produce olefins utilizing a fluidized bed of supported platinum, rhodium or nickel particles.
2. Related Art
The abundant supplies of light alkanes (methane, ethane, propane, normal butane and iso-butane) have led to greater utilization of them as feedstocks rather than fuel. The light alkanes are the preferred feed stocks for producing olefins by thermal pyrolysis. However, thermal dehydrogenation processes for olefin production are highly endothermic and require complex tube furnaces. In addition excess steam (about 50% by volume) is necessary to slow coke formation, and the products contain acetylenes, diolefins and aromatics in addition to the desired olefins.
Early U.S. Pat. Nos. 3,420,911; 3,420,912; 3,440,299 and 3,428,703 disclose a moving bed solid oxidant used for oxidative dehydrogenation of organic compounds. The oxidant, a metal ferrite in a moving bed is contacted with the organic compound in the presence of oxygen and steam in a reaction zone to remove hydrogen producing compounds of higher unsaturation. The oxygen deficient bed moves to a reoxidation zone and hence back to the rezone and so forth.
Okagami et al in U.S. Pat. No. 3,541,179 suggest utilizing copper, manganese, chromium, vanadium, zinc, silver or cadmium supported on a refractory material and in a fluidized mode for oxidative dehydrogenation of hydrocarbons. Brophy, et al in U.S. Pat. No. 4,767,569 suggest an oxidative dehydrogenation process utilizing an inert particulate catalyst in a spouting bed mode wherein the hydrocarbon and oxygen stream are fed at a flow rate sufficient to produce a spouting action of the bed material whereby at least a part of the particulate catalyst is thrown up above the bed surface and subsequently falls back into the bed.
Freide, et al in U.S. Pat. No. 4,940,826 suggest utilizing a particulate catalyst having a platinum group metal supported thereon in lieu of the inert material of Brophy to produce olefins when feeding ethane and higher alkanes.